Support for the bereaved has a shape almost nobody notices until they are inside it: an overwhelming flood for two weeks, a thinning through the first month, and then near-total silence — arriving at roughly the moment the shock wears off and the actual grief begins. People are most alone in this at precisely the point everyone assumes they are getting better.
Which makes the late message disproportionately valuable. It costs you one line and it does something none of the early ones could: it proves that someone else still remembers, at a point when the griever has started to suspect that no one does.
Say the name, unprompted. Months in, the fear that their person is being forgotten is often sharper than the loss itself. “I thought of Ellen today — someone at work made that terrible joke she used to make” is not a reminder of pain. It is evidence that she was real and is still being carried by somebody else.
Do not check whether it is still okay to mention them. Asking “is it alright if I bring him up?” makes the griever manage your caution. Just bring him up.
Mark the dates nobody else marks. The anniversary of the death, the birthday, the first Christmas, their wedding anniversary. Everyone remembers the funeral; almost nobody remembers the second August.
Expect it to be worse than they let on. By month four most people have learned that the honest answer makes others uncomfortable, so they have a stock reply ready. “How are you doing — really?” with a pause afterwards is often the first opening they have had in weeks.
And do not apologize for the timing. Not “sorry, I know this is out of the blue,” not “I should have written sooner.” That converts your message into a small obligation to forgive you. Just send the line.
One sentence, sent whenever you happen to think of it, no reply required: “I was thinking about your dad today. No need to write back — I just didn’t want you to think he’d been forgotten.”